can't transform the object
Looking at the chain link icon beside the object name, you didn't Append the object but Linked it.

You can't move linked objects directly, you have to use a proxy (old way) or a library override (new way).
If you want to retain the link to the original file, right click on the object in the outliner, then go to ID Data &gt; Add Library Override.
The outliner should look like this :

If you want to have the object act independently of the original file, like it would if it had been appended, you need to right click on the object in the outliner, then go to ID Data &gt; Make Local.
The outliner should look like this :